The present invention relates to gasification and other processes which require distribution of relatively high (e.g. to 2000.degree. F.) temperature reacting and fluidizing gases into cooler fluidized beds and more particularly, to a coal gasification process wherein the fluidized bed comprises coal particles.
Typically in gasification processes and more specifically coal gasification, a high temperature gas distributor is required for distributing the fluidizing and reaction gases to the fluid bed of coal particles. It is important in these processes for the fluidizing gases entering the bed to have a relatively high pressure drop in order to achieve good distribution to and fluidization of the bed. Standard distributors have employed grid gas distribution arrangements having caps which are directly exposed to high temperature gases and associated corrosion. Other distributors have included the use of a uniform diameter opening which causes the fluidizing gas to enter the bed at such a high velocity to obtain the necessary pressure drop that attrition of the coal particles in the bed takes place.
Other prior art includes the gas discharge nozzle illustrated in U.S. Pat. No. 3,974,091 wherein the gas discharge nozzle for the distributor comprises a stepped cylindrical configuration for an unlined gas outlet opening. This design typifies the prior art which cannot withstand the high inlet gas tempertures and high pressure drops which are encountered in certain processes.